title: Two-generation effects of the chitin synthesis inhibitor, teflubenzuron, on the aquatic midge Chironomus riparius.
abstract: Teflubenzuron, a chitin synthesis inhibitor was used in a two-generation test with Chironomus riparius (Insecta) to assess effects over a full life cycle from the first-instar larvae in the parental (P) generation until emergence in the subsequent F1 generation. Sediment spiked with teflubenzuron ranging from 10 to 390.6 μg/kg sediment dry weight (dw) was used. EC₅₀-values for fecundity and fertility were 112.7 and 74.5 μg/kg dw, respectively. Significant adverse effects were observed compared to the solvent control for emergence rate (P < 0.01) and also for developmental rate. No observed effect concentrations values were lower for emergence rate in the F1 generation (62.5 μg/kg dw) than in the P generation (100 μg/kg dw), demonstrating that the F1 generation was more affected than the P generation. Thus, this two-generation test may help detecting population level effects as an amendment to the risk assessment for chronic exposures to endocrine disrupting compounds.
authors.affiliation: Institute for Environmental Sciences, University of Koblenz-Landau, Landau (Pfalz), Germany. tassou@uni-landau.de
authors.forename: Koffi T
authors.initials: KT
authors.lastname: Tassou
authors.forename: Ralf
authors.initials: R
authors.lastname: Schulz
mesh_terms: D000818:Animals; D001549:Benzamides / Q000633:toxicity*; D002683:Chironomidae / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D002686:Chitin / Q000037:antagonists & inhibitors* / Q000378:metabolism; D005298:Fertility / Q000187:drug effects; D007605:Juvenile Hormones / Q000633:toxicity*; D007814:Larva / Q000187:drug effects; D008018:Life Cycle Stages / Q000187:drug effects; D012744:Sex Ratio; D014874:Water Pollutants, Chemical / Q000633:toxicity
chemical_list: D001549:Benzamides; D007605:Juvenile Hormones; D014874:Water Pollutants, Chemical; D002686:Chitin; C052595:teflubenzuron